I am working with six different LED Spot II moving head fixtures, and they are all having the same issue. They will randomly lock up and not respond to any DMX control signals. The only way to fix it is with either a power cycle, or to wait until the fixture automatically does a fixture reset. After which, everything is back to normal until it locks up again. It only seems to effect the LED II fixtures, and not our LED III fixtures. Is this a common issue? Is there a way to fix this? I appreciate any and all advice. Thanks!